This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The objective of this study, funded by K23HL092229, is to compare carotid MR plaque imaging at 7 Tesla (7T) with histological controls using carotid endarterectomy specimens. To date, most carotid plaque imaging has been conducted at lower magnetic field strengths (i.e. 1.5 or 3.0 Tesla) and little is known about the performance of carotid plaque imaging at 7T. Magnetic field strength is a primary determinant of image quality. However, magnetic field strength is also associated with specific changes to the technical aspects of the pulse sequences. For example, higher magnetic fields have a significant effect on T1 relaxation times of different tissues, resulting in significant differences in signal intensities. Therefore, we hypothesize that carotid plaque imaging at 7T will be associated with several technical improvements in the image quality: Hypothesis #1: In comparison to previously reported findings at 1.5 and 3.0T, carotid MRI at 7T will be associated with higher signal to noise ratios, improved spatial resolution, and reduced scan times. Hypothesis #2: In comparison to previously reported findings at 1.5 and 3.0T, carotid MRI at 7T will be associated with longer T1 times for carotid plaque components (i.e. hemorrhage, fibrous tissue, lipid-rich necrotic core). Hypothesis #3: In comparison to previously reported findings at 1.5 and 3.0T, carotid MRI at 7T will be associated with better agreement with histology as the gold standard using standard statistical techniques. Because these analyses will be performed on carotid endarterectomy specimens that have already been surgically removed (i.e. surgical waste), the present study exposes the patients to no risk. In contrast, because of the clinical importance of improved techniques for carotid plaque characterization, the present study has the potential to improve the ability to measure plaque characteristics non-invasively using MRI techniques. In the future, significant improvements in technique could translate into an overall benefit for patients, allowing for better patient selection to guide treatment strategies in patients with carotid artery disease.